Bicycles are more popular than ever as both a means of exercise and with seemingly ever increasing gas prices, as an energy efficient means of transportation. One of the biggest problems with bicycle transportation is that it is typically limited to transporting a single person. This can be especially problematic for families wherein a mother and/or father may want to cycle to the store or get some exercise but she/he cannot because she/he is watching the child or children. With very young children, a child bicycle seat can often be utilized wherein the seat is bolted to the bicycle behind the cyclist; however, these types of seats are only suitable for very small children as the center of gravity of the bicycle, cyclist and child is raised as the weight of the child increases negatively impacting the bicycles stability. Also known in the art are various types of bicycle trailers that have one or more wheels and are pulled behind a bicycle. Each of the known types of trailers suffers from one or more deficiencies that have negatively impacted its acceptance in the marketplace.
In describing both prior art bicycle trailers and embodiments of the present invention, the following terminology will be utilized: (a) towing bicycle will be referred to as the “tow cycle”; (b) an adult, or rider, of the tow cycle will be referred to as the “principal rider”; (c) the riders or passengers of a bicycle trailer, who may be adults or children, will be referred to as “passenger(s)”, a “child” or “children”; and (d) the tow bicycle in combination with the bicycle trailer will collectively be referred to as the “combined cycle”.
There are at least three types of trailer designs known in the art, which enable adults to tow one or more children behind a bicycle. These include (a) buggy trailers, (b) upright trailer cycles, and (c) exercise trailers. Some of the pros and cons of each type are discussed below.
Buggy trailers (FIG. 16) generally comprise a seat or compartment supported by wheels on either side and boom or other means to secure the trailer to a tow cycle in front. Buggy trailers usually offer a safety restraint, a sitting passenger position, and stability provided by the wide track of a two-wheeled design.
However, the very wide width or track of the side by side two wheel design that gives it a high degree of straight line stability also presents several problems or issues. First, many sidewalks and paths cannot accommodate the buggy trailer as they are not wide enough. Even if the sidewalk or path is wider than the track of the trailer, it may not be wide enough to facilitate pedestrians and bicyclists coming from an opposite direction to easily pass. Secondly, buggy trailers hinder the emergency maneuverability of the combined cycle. Rapid turns or lane changes can cause the trailer to tip up onto one wheel possibly taking the tow cycle with it. Further, the two additional wheels greatly increase rolling friction and the wide stance increases the aerodynamic drag of the combined cycle lowering the cycle's overall efficiency and potential speed. Since children typically cannot participate in propulsion, buggy trailers require additional energy output from the principle rider making them even more difficult to tow. Finally, because of their lack of participation in the combined cycle's propulsion, children and other passengers may quickly become bored and as such only tolerate these types of trailers for short durations, limiting the distance that the principal rider can travel.
Another commercially available trailer, the upright trailer cycle 12 & 14 (FIGS. 14 and 15), has a single rear wheel and allows a principal rider to tow one or two children who can contribute to propulsion of the combined cycle.
While allowing passengers to participate in propulsion, upright trailer cycles 12 & 14 usually lack safety restraints to secure the child to the trailer, making them less suitable for use with younger children. The upright position does not easily allow the child to rest comfortably while being towed for extended durations. Use of an upright trailer cycle requires the passenger to focus on the terrain and the principal rider's direction of travel to prevent falling off the trailer cycle, due to unexpected turns or travel over uneven surfaces. To be operated safely, upright trailer cycles generally require the child to interface with the trailer bicycle at three points while riding: 1) hands on the handlebars, 2) buttocks on the saddle, and 3) feet on the pedals. Should the child remove his or her hands, buttocks, or feet from the trailer bicycle, the child increases their risk of becoming separated from the trailer bicycle in the event that the principal rider unexpectedly changes direction or travels over an uneven surface.
Upright trailer cycles are not designed to minimize forces transferred from the trailer to the tow cycle and as such allow significant forces to be transferred from the trailer to the tow cycle. Consequently, passengers on an upright trailer cycle can often override the control of the principal rider. Forces from the passenger's body movements, even pedaling motion, may result in unpredictable control of the tow cycle which can potentially lead to accidents.
It should be noted that children, while on trailers, are known to unpredictably exert forces perpendicular to the direction of travel by quickly moving their bodies to turn and view passing objects, or to excitedly move side-to-side to look around the tow cycle. Two children on a trailer exert additional side-to-side force and often behave more unpredictably due to their interaction with each other. Prior art trailer cycles having the benefit of a single rear wheel are not designed to minimize the transfer of these side-to-side forces from the trailer to the tow cycle.
At least one company unsuccessfully provided a two-passenger, upright trailer bicycle 14 (Reference FIG. 15). The two-person, upright trailer bicycle was sold in 1998 for about one year. This two-passenger, upright trailer cycle multiplied the unstable nature of the device and in studies even a skilled cyclist was unable to safely control the two-passenger upright trailer cycle. Consequently, production of the two-passenger upright trailer cycle was discontinued, reinforcing its inoperability. After nearly a decade, the two-passenger upright-type trailer cycle has been reintroduced to the market. The product is experiencing insignificant sales as retailers are familiar with the safety concerns associated with the cycle's unpredictable handling characteristics.
The exercise trailer in U.S. Pat. No. 5,269,548, to Milligan, is intended to provide exercise to the handicapped. The design employs a wide, two-wheeled configuration with a passenger resting between the rear wheels. This configuration is relatively complex to fabricate and does not support the convenient use of standard bicycle components or gears to accommodate riding at different speeds over varied terrain.